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Xie J, Yi Q, Wu Y, Zheng Y, Liu Y, Macerollo A, Fu H, Xu Y, Zhang J, Behera A, Fan C, Frangi AF, Liu J, Lu Q, Qi H, Zhao Y. Deep segmentation of OCTA for evaluation and association of changes of retinal microvasculature with Alzheimer's disease and mild cognitive impairment. Br J Ophthalmol 2024; 108:432-439. [PMID: 36596660 PMCID: PMC10894818 DOI: 10.1136/bjo-2022-321399] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 12/17/2022] [Indexed: 01/05/2023]
Abstract
BACKGROUND Optical coherence tomography angiography (OCTA) enables fast and non-invasive high-resolution imaging of retinal microvasculature and is suggested as a potential tool in the early detection of retinal microvascular changes in Alzheimer's Disease (AD). We developed a standardised OCTA analysis framework and compared their extracted parameters among controls and AD/mild cognitive impairment (MCI) in a cross-section study. METHODS We defined and extracted geometrical parameters of retinal microvasculature at different retinal layers and in the foveal avascular zone (FAZ) from segmented OCTA images obtained using well-validated state-of-the-art deep learning models. We studied these parameters in 158 subjects (62 healthy control, 55 AD and 41 MCI) using logistic regression to determine their potential in predicting the status of our subjects. RESULTS In the AD group, there was a significant decrease in vessel area and length densities in the inner vascular complexes (IVC) compared with controls. The number of vascular bifurcations in AD is also significantly lower than that of healthy people. The MCI group demonstrated a decrease in vascular area, length densities, vascular fractal dimension and the number of bifurcations in both the superficial vascular complexes (SVC) and the IVC compared with controls. A larger vascular tortuosity in the IVC, and a larger roundness of FAZ in the SVC, can also be observed in MCI compared with controls. CONCLUSION Our study demonstrates the applicability of OCTA for the diagnosis of AD and MCI, and provides a standard tool for future clinical service and research. Biomarkers from retinal OCTA images can provide useful information for clinical decision-making and diagnosis of AD and MCI.
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Affiliation(s)
- Jianyang Xie
- Cixi Institute of Biomedical Engineering, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang, China
| | - Quanyong Yi
- Ningbo Eye Hospital, Ningbo, Zhejiang, China
| | - Yufei Wu
- Department of Ophthalmology, The Affiliated People's Hospital of Ningbo University, Ningbo, Zhejiang, China
| | - Yalin Zheng
- Department of Eye and Vision Science, University of Liverpool, Liverpool, UK
| | - Yonghuai Liu
- Department of Computer Science, Edge Hill University, Ormskirk, UK
| | - Antonella Macerollo
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK
| | - Huazhu Fu
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), Singapore
| | - Yanwu Xu
- Intelligent Healthcare Unit, Baidu Inc, Beijing, Haidian, China
| | - Jiong Zhang
- Cixi Institute of Biomedical Engineering, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang, China
| | - Ardhendu Behera
- Department of Computer Science, Edge Hill University, Ormskirk, UK
| | - Chenlei Fan
- Department of Neurology, The Affiliated People's Hospital of Ningbo University, Ningbo, Zhejiang, China
| | | | - Jiang Liu
- Department of Computer Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, China
| | - Qinkang Lu
- Department of Ophthalmology, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Hong Qi
- Ophthalmology, Peking University Third Hospital, Haidian, Beijing, China
| | - Yitian Zhao
- Cixi Institute of Biomedical Engineering, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang, China
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Yoon JM, Lim CY, Noh H, Nam SW, Jun SY, Kim MJ, Song MY, Jang H, Kim HJ, Seo SW, Na DL, Chung MJ, Ham DI, Kim K. Enhancing foveal avascular zone analysis for Alzheimer's diagnosis with AI segmentation and machine learning using multiple radiomic features. Sci Rep 2024; 14:1841. [PMID: 38253722 PMCID: PMC10810355 DOI: 10.1038/s41598-024-51612-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Accepted: 01/07/2024] [Indexed: 01/24/2024] Open
Abstract
We propose a hybrid technique that employs artificial intelligence (AI)-based segmentation and machine learning classification using multiple features extracted from the foveal avascular zone (FAZ)-a retinal biomarker for Alzheimer's disease-to improve the disease diagnostic performance. Imaging data of optical coherence tomography angiography from 37 patients with Alzheimer's disease and 48 healthy controls were investigated. The presence or absence of brain amyloids was confirmed using amyloid positron emission tomography. In the superficial capillary plexus of the angiography scans, the FAZ was automatically segmented using an AI method to extract multiple biomarkers (area, solidity, compactness, roundness, and eccentricity), which were paired with clinical data (age and sex) as common correction variables. We used a light-gradient boosting machine (a light-gradient boosting machine is a machine learning algorithm based on trees utilizing gradient boosting) to diagnose Alzheimer's disease by integrating the corresponding multiple radiomic biomarkers. Fivefold cross-validation was applied for analysis, and the diagnostic performance for Alzheimer's disease was determined by the area under the curve. The proposed hybrid technique achieved an area under the curve of [Formula: see text]%, outperforming the existing single-feature (area) criteria by over 13%. Furthermore, in the holdout test set, the proposed technique exhibited a 14% improvement compared to single features, achieving an area under the curve of 72.0± 4.8%. Based on these facts, we have demonstrated the effectiveness of our technology in achieving significant performance improvements in FAZ-based Alzheimer's diagnosis research through the use of multiple radiomic biomarkers (area, solidity, compactness, roundness, and eccentricity).
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Affiliation(s)
- Je Moon Yoon
- Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea
| | - Chae Yeon Lim
- Department of Medical Device Management and Research, SAIHST, Sungkyunkwan University, Seoul, 06351, Republic of Korea
| | - Hoon Noh
- Hangil Eye Hospital, 35 Bupyeong-daero, Bupyeong-gu, Incheon, 21388, Republic of Korea
| | - Seung Wan Nam
- Hangil Eye Hospital, 35 Bupyeong-daero, Bupyeong-gu, Incheon, 21388, Republic of Korea
- Department of Ophthalmology, Catholic Kwandong University College of Medicine, 35 Bupyeong-daero, Bupyeong-gu, Incheon, 21388, Republic of Korea
| | - Sung Yeon Jun
- Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea
| | - Min Ji Kim
- Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea
| | - Mi Yeon Song
- Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea
| | - Hyemin Jang
- Alzheimer's Disease Convergence Research Center, Samsung Medical Center, Seoul, Republic of Korea
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea
- Neuroscience Center, Samsung Medical Center, Seoul, Republic of Korea
- Department of Digital Health, Samsung Advanced Institute for Health Sciences & Technology, Sungkyunkwan University, Seoul, Republic of Korea
| | - Hee Jin Kim
- Alzheimer's Disease Convergence Research Center, Samsung Medical Center, Seoul, Republic of Korea
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea
| | - Sang Won Seo
- Alzheimer's Disease Convergence Research Center, Samsung Medical Center, Seoul, Republic of Korea
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea
- Neuroscience Center, Samsung Medical Center, Seoul, Republic of Korea
| | - Duk L Na
- Alzheimer's Disease Convergence Research Center, Samsung Medical Center, Seoul, Republic of Korea
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea
- Happymind Clinic, Seoul, Republic of Korea
| | - Myung Jin Chung
- Department of Data Convergence and Future Medicine, Sungkyunkwan University School of Medicine, Suwon, 16419, Republic of Korea
- Department of Radiology and AI Research Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea
| | - Don-Il Ham
- Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea.
| | - Kyungsu Kim
- Medical AI Research Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, 06351, Republic of Korea.
- Department of Data Convergence and Future Medicine, Sungkyunkwan University School of Medicine, Suwon, 16419, Republic of Korea.
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Li C, Zhu X, Yang K, Ju Y, Shi K, Xiao Y, Su B, Lu F, Cui L, Li M. Relationship of retinal capillary plexus and ganglion cell complex with mild cognitive impairment and dementia. Eye (Lond) 2023; 37:3743-3750. [PMID: 37270614 PMCID: PMC10698172 DOI: 10.1038/s41433-023-02592-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 05/08/2023] [Accepted: 05/17/2023] [Indexed: 06/05/2023] Open
Abstract
OBJECTIVE To investigate relationship of the retinal capillary plexus (RCP) and ganglion cell complex (GCC) with mild cognitive impairment (MCI) and dementia in a community-based study1. METHODS This cross-sectional study incorporated the participants of the Jidong Eye Cohort Study. Optical coherence tomography angiography was performed to obtain RCP vessel density and GCC thickness with detailed segments. The Mini-mental State Examination and Montreal Cognitive Assessment were used to assess cognitive status by professional neuropsychologists. Participants were thus divided into three groups: normal, mild cognitive impairment, and dementia. Multivariable analysis was used to measure relationship of ocular parameters with cognitive impairment. RESULTS Of the 2678 participants, the mean age was 44.1 ± 11.7 years. MCI and dementia occurred in 197 (7.4%) and 80 (3%) participants, respectively. Compared to the normal group, the adjusted odds ratio (OR) with the 95% confidence interval was 0.76 (0.65-0.90) for the correlation of lower deep RCP with MCI. We found the following items significantly associated with dementia compared with the normal group: a superficial (OR, 0.68 [0.54-0.86]) and deep (OR, 0.75 [0.57-0.99]) RCP, as well as the GCC (OR, 0.68 [0.54-0.85]). Compared to the MCI group, those with dementia had decreased GCC (OR, 0.75 [0.58-0.97]). CONCLUSIONS Decreased deep RCP density was associated with MCI. Decreased superficial and deep RCP and the thin GCC were correlated with dementia. These implied that the retinal microvasculature may develop into a promising non-invasive imaging marker to predict severity of cognitive impairment.
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Affiliation(s)
- Chunmei Li
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Xiaoxuan Zhu
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Kai Yang
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Ying Ju
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Keai Shi
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Yunfan Xiao
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Binbin Su
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Fan Lu
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China.
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China.
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China.
| | - Lele Cui
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China.
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China.
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China.
| | - Ming Li
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China.
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China.
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China.
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Greene AN, Solomon MB, Privette Vinnedge LM. Novel molecular mechanisms in Alzheimer's disease: The potential role of DEK in disease pathogenesis. Front Aging Neurosci 2022; 14:1018180. [PMID: 36275000 PMCID: PMC9582447 DOI: 10.3389/fnagi.2022.1018180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
Alzheimer's disease and age-related dementias (AD/ADRD) are debilitating diseases that exact a significant physical, emotional, cognitive, and financial toll on the individual and their social network. While genetic risk factors for early-onset AD have been identified, the molecular and genetic drivers of late-onset AD, the most common subtype, remain a mystery. Current treatment options are limited for the 35 million people in the United States with AD/ADRD. Thus, it is critically important to identify novel molecular mechanisms of dementia-related pathology that may be targets for the development of new interventions. Here, we summarize the overarching concepts regarding AD/ADRD pathogenesis. Then, we highlight one potential molecular driver of AD/ADRD, the chromatin remodeling protein DEK. We discuss in vitro, in vivo, and ex vivo findings, from our group and others, that link DEK loss with the cellular, molecular, and behavioral signatures of AD/ADRD. These include associations between DEK loss and cellular and molecular hallmarks of AD/ADRD, including apoptosis, Tau expression, and Tau hyperphosphorylation. We also briefly discuss work that suggests sex-specific differences in the role of DEK in AD/ADRD pathogenesis. Finally, we discuss future directions for exploiting the DEK protein as a novel player and potential therapeutic target for the treatment of AD/ADRD.
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Affiliation(s)
- Allie N. Greene
- Neuroscience Graduate Program, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Matia B. Solomon
- Neuroscience Graduate Program, University of Cincinnati College of Medicine, Cincinnati, OH, United States
- Department of Psychology, University of Cincinnati, Cincinnati, OH, United States
| | - Lisa M. Privette Vinnedge
- Division of Oncology, Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, United States
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Farzinvash Z, Abutorabi-Zarchi M, Manaviat M, Zare Mehrjerdi H. Retinal Ganglion Cell Complex in Alzheimer Disease: Comparing Ganglion Cell Complex and Central Macular Thickness in Alzheimer Disease and Healthy Subjects Using Spectral Domain-Optical Coherence Tomography. Basic Clin Neurosci 2022; 13:675-684. [PMID: 37313022 PMCID: PMC10258592 DOI: 10.32598/bcn.2021.2040.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 06/08/2021] [Accepted: 06/12/2021] [Indexed: 10/17/2023] Open
Abstract
Introduction Alzheimer disease (AD) is the most common form of dementia worldwide. The modalities to diagnose AD are generally expensive and limited. Both the central nervous system (CNS) and the retina are derived from the cranial neural crest; therefore, changes in retinal layers may reflect changes in the CNS tissue. Optical coherence tomography (OCT) machine can show delicate retinal layers and is widely used for retinal disorders. This study aims to find a new biomarker to help clinicians diagnose AD via retinal OCT examination. Methods After considering the inclusion and exclusion criteria, 25 patients with mild and moderate AD and 25 healthy subjects were enrolled in the study. OCT was done for all eyes. The central macular thickness (CMT) and the ganglion cell complex (GCC) thickness were calculated. The groups were compared using the SPSS software, v. 22. Results Both GCC thickness and CMT were significantly decreased in patients with AD when compared to healthy age- and sex-matched individuals. Conclusion Retinal changes, specifically CMT and GCC thickness, may reflect the AD process in the brain. OCT can be considered a non-invasive and inexpensive method to help diagnose AD.
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Affiliation(s)
- Zahra Farzinvash
- Department of Ophthalmology, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Marzie Abutorabi-Zarchi
- Department of Neurology, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Masoudreza Manaviat
- Department of Ophthalmology, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Habib Zare Mehrjerdi
- Department of Ophthalmology, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
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Molecular Signatures of Mitochondrial Complexes Involved in Alzheimer’s Disease via Oxidative Phosphorylation and Retrograde Endocannabinoid Signaling Pathways. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:9565545. [PMID: 35432724 PMCID: PMC9006080 DOI: 10.1155/2022/9565545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 03/22/2022] [Indexed: 11/17/2022]
Abstract
Objective The inability to intervene in Alzheimer's disease (AD) forces the search for promising gene-targeted therapies. This study was aimed at exploring molecular signatures and mechanistic pathways to improve the diagnosis and treatment of AD. Methods Microarray datasets were collected to filter differentially expressed genes (DEGs) between AD and nondementia controls. Weight gene correlation network analysis (WGCNA) was employed to analyze the correlation of coexpression modules with AD phenotype. A global regulatory network was established and then visualized using Cytoscape software to determine hub genes and their mechanistic pathways. Receiver operating characteristic (ROC) analysis was conducted to estimate the diagnostic performance of hub genes in AD prediction. Results A total of 2,163 DEGs from 13,049 background genes were screened in AD relative to nondementia controls. Among the six coexpression modules constructed by WGCNA, DEGs of the key modules with the strongest correlation with AD were extracted to build a global regulatory network. According to the Maximal Clique Centrality (MCC) method, five hub genes associated with mitochondrial complexes were chosen. Further pathway enrichment analysis of hub genes, such as oxidative phosphorylation and retrograde endocannabinoid signaling, was identified. According to the area under the curve (AUC) of about 70%, each hub gene exhibited a good diagnostic performance in predicting AD. Conclusions Our findings highlight the perturbation of mitochondrial complexes underlying AD onset, which is mediated by molecular signatures involved in oxidative phosphorylation (COX5A, NDUFAB1, SDHB, UQCRC2, and UQCRFS1) and retrograde endocannabinoid signaling (NDUFAB1) pathways.
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Integrative genomic analysis of PPP3R1 in Alzheimer's disease: a potential biomarker for predictive, preventive, and personalized medical approach. EPMA J 2021; 12:647-658. [PMID: 34956428 DOI: 10.1007/s13167-021-00261-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 10/18/2021] [Indexed: 01/26/2023]
Abstract
Alzheimer's disease (AD) is associated with abnormal calcium signaling, a pathway regulated by the calcium-dependent protein phosphatase. This study aimed to investigate the molecular function of protein phosphatase 3 regulatory subunit B (PPP3R1) underlying AD, which may provide novel insights for the predictive diagnostics, targeted prevention, and personalization of medical services in AD by targeting PPP3R1. A total of 1860 differentially expressed genes (DEGs) from 13,049 background genes were overlapped in AD/control and PPP3R1-low/high cohorts. Based on these DEGs, six co-expression modules were constructed by weight gene correlation network analysis (WGCNA). The turquoise module had the strongest correlation with AD and low PPP3R1, in which DEGs participated in axon guidance, glutamatergic synapse, long-term potentiation (LTP), mitogen-activated protein kinase (MAPK), Ras, and hypoxia-inducible factor 1 (HIF-1) signaling pathways. Furthermore, the cross-talking pathways of PPP3R1, such as axon guidance, glutamatergic synapse, LTP, and MAPK signaling pathways, were identified in the global regulatory network. The area under the curve (AUC) analysis showed that low PPP3R1 could accurately predict the onset of AD. Therefore, our findings highlight the involvement of PPP3R1 in the pathogenesis of AD via axon guidance, glutamatergic synapse, LTP, and MAPK signaling pathways, and identify downregulation of PPP3R1 as a potential biomarker for AD treatment in the context of 3P medicine-predictive diagnostics, targeted prevention, and personalization of medical services. Supplementary Information The online version contains supplementary material available at 10.1007/s13167-021-00261-2.
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Balaji S. The transferred translocases: An old wine in a new bottle. Biotechnol Appl Biochem 2021; 69:1587-1610. [PMID: 34324237 DOI: 10.1002/bab.2230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 07/23/2021] [Indexed: 11/12/2022]
Abstract
The role of translocases was underappreciated and was not included as a separate class in the enzyme commission until August 2018. The recent research interests in proteomics of orphan enzymes, ionomics, and metallomics along with high-throughput sequencing technologies generated overwhelming data and revamped this enzyme into a separate class. This offers a great opportunity to understand the role of new or orphan enzymes in general and specifically translocases. The enzymes belonging to translocases regulate/permeate the transfer of ions or molecules across the membranes. These enzyme entries were previously associated with other enzyme classes, which are now transferred to a new enzyme class 7 (EC 7). The entries that are reclassified are important to extend the enzyme list, and it is the need of the hour. Accordingly, there is an upgradation of entries of this class of enzymes in several databases. This review is a concise compilation of translocases with reference to the number of entries currently available in the databases. This review also focuses on function as well as dysfunction of translocases during normal and disordered states, respectively.
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Affiliation(s)
- S Balaji
- Department of Biotechnology, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, Karnataka, 576 104, India
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Lemmens S, Van Craenendonck T, Van Eijgen J, De Groef L, Bruffaerts R, de Jesus DA, Charle W, Jayapala M, Sunaric-Mégevand G, Standaert A, Theunis J, Van Keer K, Vandenbulcke M, Moons L, Vandenberghe R, De Boever P, Stalmans I. Combination of snapshot hyperspectral retinal imaging and optical coherence tomography to identify Alzheimer's disease patients. Alzheimers Res Ther 2020; 12:144. [PMID: 33172499 PMCID: PMC7654576 DOI: 10.1186/s13195-020-00715-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 10/22/2020] [Indexed: 12/14/2022]
Abstract
INTRODUCTION The eye offers potential for the diagnosis of Alzheimer's disease (AD) with retinal imaging techniques being explored to quantify amyloid accumulation and aspects of neurodegeneration. To assess these changes, this proof-of-concept study combined hyperspectral imaging and optical coherence tomography to build a classification model to differentiate between AD patients and controls. METHODS In a memory clinic setting, patients with a diagnosis of clinically probable AD (n = 10) or biomarker-proven AD (n = 7) and controls (n = 22) underwent non-invasive retinal imaging with an easy-to-use hyperspectral snapshot camera that collects information from 16 spectral bands (460-620 nm, 10-nm bandwidth) in one capture. The individuals were also imaged using optical coherence tomography for assessing retinal nerve fiber layer thickness (RNFL). Dedicated image preprocessing analysis was followed by machine learning to discriminate between both groups. RESULTS Hyperspectral data and retinal nerve fiber layer thickness data were used in a linear discriminant classification model to discriminate between AD patients and controls. Nested leave-one-out cross-validation resulted in a fair accuracy, providing an area under the receiver operating characteristic curve of 0.74 (95% confidence interval [0.60-0.89]). Inner loop results showed that the inclusion of the RNFL features resulted in an improvement of the area under the receiver operating characteristic curve: for the most informative region assessed, the average area under the receiver operating characteristic curve was 0.70 (95% confidence interval [0.55, 0.86]) and 0.79 (95% confidence interval [0.65, 0.93]), respectively. The robust statistics used in this study reduces the risk of overfitting and partly compensates for the limited sample size. CONCLUSIONS This study in a memory-clinic-based cohort supports the potential of hyperspectral imaging and suggests an added value of combining retinal imaging modalities. Standardization and longitudinal data on fully amyloid-phenotyped cohorts are required to elucidate the relationship between retinal structure and cognitive function and to evaluate the robustness of the classification model.
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Affiliation(s)
- Sophie Lemmens
- Department of Ophthalmology, University Hospitals UZ Leuven, Herestraat 49, 3000 Leuven, Belgium
- Department of Neurosciences, Research Group Ophthalmology, KU Leuven, Biomedical Sciences Group, Herestraat 49, 3000 Leuven, Belgium
- VITO (Flemish Institute for Technological Research), Health Unit, Boeretang 200, 2400 Mol, Belgium
| | - Toon Van Craenendonck
- VITO (Flemish Institute for Technological Research), Health Unit, Boeretang 200, 2400 Mol, Belgium
| | - Jan Van Eijgen
- Department of Ophthalmology, University Hospitals UZ Leuven, Herestraat 49, 3000 Leuven, Belgium
- Department of Neurosciences, Research Group Ophthalmology, KU Leuven, Biomedical Sciences Group, Herestraat 49, 3000 Leuven, Belgium
- VITO (Flemish Institute for Technological Research), Health Unit, Boeretang 200, 2400 Mol, Belgium
| | - Lies De Groef
- Neural Circuit Development and Regeneration Research Group, Department of Biology, KU Leuven, Naamsestraat 61, 3000 Leuven, Belgium
| | - Rose Bruffaerts
- Laboratory for Cognitive Neurology, Department of Neurosciences, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
- Department of Neurology, University Hospitals UZ Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Danilo Andrade de Jesus
- Department of Neurosciences, Research Group Ophthalmology, KU Leuven, Biomedical Sciences Group, Herestraat 49, 3000 Leuven, Belgium
| | | | | | - Gordana Sunaric-Mégevand
- Clinical Research Center, Mémorial A. de Rothschild, 22 Chemin Beau Soleil, 1208 Geneva, Switzerland
| | - Arnout Standaert
- VITO (Flemish Institute for Technological Research), Health Unit, Boeretang 200, 2400 Mol, Belgium
| | - Jan Theunis
- VITO (Flemish Institute for Technological Research), Health Unit, Boeretang 200, 2400 Mol, Belgium
| | - Karel Van Keer
- Department of Ophthalmology, University Hospitals UZ Leuven, Herestraat 49, 3000 Leuven, Belgium
- Department of Neurosciences, Research Group Ophthalmology, KU Leuven, Biomedical Sciences Group, Herestraat 49, 3000 Leuven, Belgium
| | - Mathieu Vandenbulcke
- Division of Psychiatry, University Hospitals Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Lieve Moons
- Neural Circuit Development and Regeneration Research Group, Department of Biology, KU Leuven, Naamsestraat 61, 3000 Leuven, Belgium
| | - Rik Vandenberghe
- Laboratory for Cognitive Neurology, Department of Neurosciences, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
- Department of Neurology, University Hospitals UZ Leuven, Herestraat 49, 3000 Leuven, Belgium
- Alzheimer Research Center KU Leuven, Leuven Brain Institute, Herestraat 49, 3000 Leuven, Belgium
| | - Patrick De Boever
- VITO (Flemish Institute for Technological Research), Health Unit, Boeretang 200, 2400 Mol, Belgium
- Hasselt University, Center of Environmental Sciences, Agoralaan, 3590 Diepenbeek, Belgium
- Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Ingeborg Stalmans
- Department of Ophthalmology, University Hospitals UZ Leuven, Herestraat 49, 3000 Leuven, Belgium
- Department of Neurosciences, Research Group Ophthalmology, KU Leuven, Biomedical Sciences Group, Herestraat 49, 3000 Leuven, Belgium
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10
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Yoon SP, Grewal DS, Thompson AC, Polascik BW, Dunn C, Burke JR, Fekrat S. Retinal Microvascular and Neurodegenerative Changes in Alzheimer's Disease and Mild Cognitive Impairment Compared with Control Participants. Ophthalmol Retina 2019; 3:489-499. [PMID: 31174670 PMCID: PMC6586560 DOI: 10.1016/j.oret.2019.02.002] [Citation(s) in RCA: 135] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 12/30/2018] [Accepted: 02/11/2019] [Indexed: 10/27/2022]
Abstract
PURPOSE Evaluate and compare the retinal microvasculature in the superficial capillary plexus (SCP) in Alzheimer's disease (AD), mild cognitive impairment (MCI), and cognitively intact controls using OCT angiography. OCT parameters were also compared. DESIGN Cross-sectional study. PARTICIPANTS Seventy eyes from 39 AD participants, 72 eyes from 37 MCI participants, and 254 eyes from 133 control participants were enrolled. METHODS Participants were imaged using Zeiss Cirrus HD-5000 with AngioPlex (Carl Zeiss Meditec, Dublin, CA) and underwent cognitive evaluation with Mini-Mental State Examination. MAIN OUTCOME MEASURES Vessel density (VD) and perfusion density (PD) in the SCP within the Early Treatment Diabetic Retinopathy Study 6-mm circle, 3-mm circle, and 3-mm ring were compared between groups. Foveal avascular zone (FAZ) area, central subfield thickness (CST), macular ganglion cell-inner plexiform layer (GC-IPL) thickness, and peripapillary retinal nerve fiber layer (RNFL) thickness were also compared. RESULTS Alzheimer's participants showed significantly decreased SCP VD and PD in the 3-mm ring (P = 0.001 and P = 0.002, respectively) and 3-mm circle (P = 0.003 and P = 0.004, respectively) and decreased SCP VD in the 6-mm circle (P = 0.047) compared with MCI and significantly decreased SCP VD and PD in the 3-mm ring (P = 0.008 and P = 0.004, respectively) and 3-mm circle (P = 0.015 and P = 0.009, respectively) and SCP PD in the 6-mm circle (P = 0.033) when compared with cognitively intact controls. There was no difference in SCP VD or PD between MCI and controls (P > 0.05). FAZ area and CST did not differ significantly between groups (P > 0.05). Alzheimer's participants showed significantly decreased GC-IPL thickness over the inferior (P = 0.032) and inferonasal (P = 0.025) sectors compared with MCI and significantly decreased GC-IPL thickness over the entire (P = 0.012), superonasal (P = 0.041), inferior (P = 0.004), and inferonasal (P = 0.006) sectors compared to controls. MCI participants showed significantly decreased temporal RNFL thickness (P = 0.04) compared with controls. CONCLUSIONS Alzheimer's participants showed significantly reduced macular VD, PD, and GC-IPL thickness compared with MCI and controls. Changes in the retinal microvasculature may mirror small vessel cerebrovascular changes in AD.
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Affiliation(s)
- Stephen P Yoon
- Department of Ophthalmology, Duke University, Durham, North Carolina
| | - Dilraj S Grewal
- Department of Ophthalmology, Duke University, Durham, North Carolina
| | - Atalie C Thompson
- Department of Ophthalmology, Duke University, Durham, North Carolina
| | - Bryce W Polascik
- Department of Ophthalmology, Duke University, Durham, North Carolina
| | - Cynthia Dunn
- Department of Neurology, Duke University, Durham, North Carolina
| | - James R Burke
- Department of Neurology, Duke University, Durham, North Carolina
| | - Sharon Fekrat
- Department of Ophthalmology, Duke University, Durham, North Carolina.
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11
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Heinemeyer T, Stemmet M, Bardien S, Neethling A. Underappreciated Roles of the Translocase of the Outer and Inner Mitochondrial Membrane Protein Complexes in Human Disease. DNA Cell Biol 2018; 38:23-40. [PMID: 30481057 DOI: 10.1089/dna.2018.4292] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Mitochondria are critical for cellular survival, and for their proper functioning, translocation of ∼1500 proteins across the mitochondrial membranes is required. The translocase of the outer (TOMM) and inner mitochondrial membrane (TIMM) complexes are major components of this translocation machinery. Through specific processes, preproteins and other molecules are imported, translocated, and directed to specific mitochondrial compartments for their function. In this study, we review the association of subunits of these complexes with human disease. Pathogenic mutations have been identified in the TIMM8A (DDP) and DNAJC19 (TIMM14) genes and are linked to Mohr-Tranebjærg syndrome and dilated cardiomyopathy syndrome (with and without ataxia), respectively. Polymorphisms in TOMM40 have been associated with Alzheimer's disease, frontotemporal lobar degeneration, Parkinson's disease with dementia, dementia with Lewy bodies, nonpathological cognitive aging, and various cardiovascular-related traits. Furthermore, reduced protein expression levels of several complex subunits have been associated with Parkinson's disease, Meniere's disease, and cardiovascular disorders. However, increased mRNA and protein levels of complex subunits are found in cancers. This review highlights the importance of the mitochondrial import machinery in human disease and stresses the need for further studies. Ultimately, this knowledge may prove to be critical for the development of therapeutic modalities for these conditions.
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Affiliation(s)
- Thea Heinemeyer
- Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University , Cape Town, South Africa
| | - Monique Stemmet
- Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University , Cape Town, South Africa
| | - Soraya Bardien
- Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University , Cape Town, South Africa
| | - Annika Neethling
- Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University , Cape Town, South Africa
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12
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Ocular amyloid imaging at the crossroad of Alzheimer's disease and age-related macular degeneration: implications for diagnosis and therapy. J Neurol 2018; 266:1566-1577. [PMID: 30155741 DOI: 10.1007/s00415-018-9028-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 08/18/2018] [Accepted: 08/20/2018] [Indexed: 12/17/2022]
Abstract
Alzheimer's disease (AD) and age-related macular degeneration (AMD) are important disorders of aging, but significant challenges remain in diagnosis and therapy. Amyloid-beta (Aβ), found in the brain and a defining feature of AD, has also been observed in the retina in both AD and AMD. While current diagnostic modalities for detecting Aβ in the brain are costly or invasive, Aβ in the retina can be noninvasively and conveniently imaged using modern photonic imaging systems such as optical coherence tomography (OCT). Moreover, since many of these retinal changes occur before degenerative changes can be detected in the brain, ocular amyloid biomarkers could be utilized to detect AD as well as AMD in their earliest stages when therapy may be most effective in halting disease progression. Novel technologies to quantify retinal biomarkers have the potential to facilitate early diagnosis and noninvasive monitoring of disease progression with important therapeutic implications.
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13
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Chen Y, Lim P, Rogers KA, Rutt BK, Ronald JA. In Vivo MRI of Amyloid Plaques in a Cholesterol-Fed Rabbit Model of Alzheimer’s Disease. J Alzheimers Dis 2018; 64:911-923. [DOI: 10.3233/jad-180207] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Yuanxin Chen
- Robarts Research Institute, Western University, London, ON, Canada
| | - Patrick Lim
- Robarts Research Institute, Western University, London, ON, Canada
| | - Kem A. Rogers
- Department of Anatomy and Cell Biology, Western University, London, ON, Canada
| | - Brian K. Rutt
- Department of Radiology, Stanford University, Stanford, CA, USA
| | - John A. Ronald
- Robarts Research Institute, Western University, London, ON, Canada
- Department of Medical Biophysics, Western University, London, ON, Canada
- Lawson Health Research Institute, London, ON, Canada
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14
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Kim H, Han H. Computer-Aided Multi-Target Management of Emergent Alzheimer's Disease. Bioinformation 2018; 14:167-180. [PMID: 29983487 PMCID: PMC6016757 DOI: 10.6026/97320630014167] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 04/29/2018] [Accepted: 04/30/2018] [Indexed: 12/13/2022] Open
Abstract
Alzheimer's disease (AD) represents an enormous global health burden in terms of human suffering and economic cost. AD management requires a shift from the prevailing paradigm targeting pathogenesis to design and develop effective drugs with adequate success in clinical trials. Therefore, it is of interest to report a review on amyloid beta (Aβ) effects and other multi-targets including cholinesterase, NFTs, tau protein and TNF associated with brain cell death to be neuro-protective from AD. It should be noted that these molecules have been generated either by target-based or phenotypic methods. Hence, the use of recent advancements in nanomedicine and other natural compounds screening tools as a feasible alternative for circumventing specific liabilities is realized. We review recent developments in the design and identification of neuro-degenerative compounds against AD generated using current advancements in computational multi-target modeling algorithms reflected by theragnosis (combination of diagnostic tests and therapy) concern.
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Affiliation(s)
- Hyunjo Kim
- Department of Medical Informatics, Ajou Medical University Hospital, Suwon, Kyeounggido province, South Korea
| | - Hyunwook Han
- Department of Informatics, School of Medicine, CHA University, Seongnam, South Korea
- Institute of Basic Medical Sciences, School of Medicine, CHA University, Seongnam, South Korea
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15
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Lad EM, Mukherjee D, Stinnett SS, Cousins SW, Potter GG, Burke JR, Farsiu S, Whitson HE. Evaluation of inner retinal layers as biomarkers in mild cognitive impairment to moderate Alzheimer's disease. PLoS One 2018; 13:e0192646. [PMID: 29420642 PMCID: PMC5805310 DOI: 10.1371/journal.pone.0192646] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 01/26/2018] [Indexed: 12/12/2022] Open
Abstract
Inner retina in Alzheimer's Disease (AD) may experience neuroinflammation resulting in atrophy. The objective of our study was to determine whether retinal GCIPL (ganglion cell-inner plexiform layer) or nerve fiber layer (NFL) thickness may serve as noninvasive biomarkers to diagnose AD. This cross-sectional case-control study enrolled 15 mild cognitive impairment (MCI) patients, 15 mild-moderate AD patients, and 18 cognitively normal adults. NFL and GCIPL thicknesses on optical coherence tomography (OCT) were measured using Duke Optical Coherence Tomography Retinal Analysis Program (DOCTRAP) and Spectralis software. We demonstrated that regional thicknesses of NFL or GCIPL on macular or nerve OCTs did not differ between groups. However, a multi-variate regression analysis identified macular areas with a significant thickening or thinning in NFL and GCIPL in MCI and AD patients. Our primary findings controvert previous reports of thinner NFL in moderate-to-severe AD. The areas of thickening of GCIPL and NFL in the macula adjacent to areas of thinning, as revealed by a more complex statistical model, suggest that NFL and GCIPL may undergo dynamic changes during AD progression.
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Affiliation(s)
- Eleonora M. Lad
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Dibyendu Mukherjee
- Department of Biomedical Engineering, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Sandra S. Stinnett
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Scott W. Cousins
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Guy G. Potter
- Joseph and Kathleen Bryan Alzheimer's Disease Research Center, Durham, North Carolina, United States of America
| | - James R. Burke
- Joseph and Kathleen Bryan Alzheimer's Disease Research Center, Durham, North Carolina, United States of America
| | - Sina Farsiu
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States of America
- Department of Biomedical Engineering, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Heather E. Whitson
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States of America
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America
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16
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PKR Inhibition Rescues Memory Deficit and ATF4 Overexpression in ApoE ε4 Human Replacement Mice. J Neurosci 2015; 35:12986-93. [PMID: 26400930 DOI: 10.1523/jneurosci.5241-14.2015] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Sporadic Alzheimer's disease (AD) is an incurable neurodegenerative disease with clear pathological hallmarks, brain dysfunction, and unknown etiology. Here, we tested the hypothesis that there is a link between genetic risk factors for AD, cellular metabolic stress, and transcription/translation regulation. In addition, we aimed at reversing the memory impairment observed in a mouse model of sporadic AD. We have previously demonstrated that the most prevalent genetic risk factor for AD, the ApoE4 allele, is correlated with increased phosphorylation of the translation factor eIF2α. In the present study, we tested the possible involvement of additional members of the eIF2α pathway and identified increased mRNA expression of negative transcription factor ATF4 (aka CREB2) both in human and a mouse model expressing the human ApoE4 allele. Furthermore, injection of a PKR inhibitor rescued memory impairment and attenuated ATF4 mRNA increased expression in the ApoE4 mice. The results propose a new mechanism by which ApoE4 affects brain function and further suggest that inhibition of PKR is a way to restore ATF4 overexpression and memory impairment in early stages of sporadic AD. Significance statement: ATF4 mRNA relative quantities are elevated in ApoE4 allele carriers compared with noncarrier controls. This is true also for the ApoE ε4 human replacement mice. ApoE4 mice injected with PKR inhibitor (PKRi) demonstrate a significant reduction in ATF4 expression levels 3 h after one injection of PKRi. Treatment of ApoE4 human replacement mice with the PKRi before learning rescues the memory impairment of the ApoE4 AD model mice. We think that these results propose a new mechanism by which ApoE4 affects brain function and suggest that inhibition of PKR is a way to restore memory impairment in early stages of sporadic AD.
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17
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Crowdsourced analysis of clinical trial data to predict amyotrophic lateral sclerosis progression. Nat Biotechnol 2014; 33:51-7. [DOI: 10.1038/nbt.3051] [Citation(s) in RCA: 143] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Accepted: 09/23/2014] [Indexed: 12/12/2022]
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18
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Association of TOMM40 Polymorphisms with Late-Onset Alzheimer’s Disease in a Northern Han Chinese Population. Neuromolecular Med 2013; 15:279-87. [DOI: 10.1007/s12017-012-8217-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 12/22/2012] [Indexed: 02/08/2023]
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19
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Caselli RJ, Reiman EM. Characterizing the preclinical stages of Alzheimer's disease and the prospect of presymptomatic intervention. J Alzheimers Dis 2013; 33 Suppl 1:S405-16. [PMID: 22695623 PMCID: PMC3628721 DOI: 10.3233/jad-2012-129026] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Studies of asymptomatic carriers of genes that are known to predispose to Alzheimer's disease (AD) have facilitated the characterization of preclinical AD. The most prevalent genetic risk factor is the ε4 allele of apolipoprotein E (APOE). Neuropathological studies of young deceased ε4 carriers have shown modest but abnormal amounts of neocortical amyloid and medial temporal neurofibrillary tangles that is also reflected in cerebrospinal fluid (CSF) biomarkers, amyloid-β, and phospho-tau in particular. MRI studies have shown progressive hippocampal and gray matter atrophy with the advent of mild cognitive impairment (MCI), and fluorodeoxyglucose PET scans show reduced cerebral metabolism in posterior cingulate and related AD regions evident even in 30 year olds. Cerebral amyloidosis disclosed by more recent amyloid ligand PET studies in asymptomatic 60 year olds increases in parallel with ε4 gene dose. Longitudinal neuropsychological studies have revealed accelerated memory decline in ε4 carriers beginning around age 55-60 years whose severity again parallels ε4 gene dose. The clinico-pathological correlation of declining memory and AD-like neuropathological change defines preclinical AD and has set the stage for the accelerated evaluation of presymptomatic AD treatments. In this article, we briefly consider some of the earliest detectable changes associated with the predisposition to AD, and some of the prevention trial strategies that have been proposed to help find treatments to reduce the risk, postpone the onset of, or completely prevent AD symptoms as soon as possible.
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20
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TOMM40 in Cerebral Amyloid Angiopathy Related Intracerebral Hemorrhage: Comparative Genetic Analysis with Alzheimer's Disease. Transl Stroke Res 2012; 3:102-12. [PMID: 24323865 DOI: 10.1007/s12975-012-0161-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Revised: 03/13/2012] [Accepted: 03/21/2012] [Indexed: 01/15/2023]
Abstract
Cerebral amyloid angiopathy (CAA) related intracerebral hemorrhage (ICH) is a devastating form of stroke with no known therapies. Clinical, neuropathological, and genetic studies have suggested both overlap and divergence between the pathogenesis of CAA and the biologically related condition of Alzheimer's disease (AD). Among the genetic loci associated with AD are APOE and TOMM40, a gene in close proximity to APOE. We investigate here whether variants within TOMM40 are associated with CAA-related ICH and CAA neuropathology. Using cohorts from the Massachusetts General Hospital (MGH) and the Alzheimer's Disease Neuroimaging Initiative (ADNI), we designed a comparative analysis of high-density SNP genotype data for CAA-related ICH and AD. APOE ε4 was associated with CAA-related ICH and AD, while APOE ε2 was protective in AD but a risk factor for CAA. A total of 14 SNPs within TOMM40 were associated with AD (p < 0.05 after multiple testing correction), but not CAA-related ICH (all p > 0.20); as a result, all AD-associated SNPs within TOMM40 showed heterogeneity of effect in CAA-related ICH (BD p < 0.001). Analysis of CAA neuropathology in the Religious Orders Study (ROS) and Rush Memory and Aging Project (MAP), however, found that neuritic plaque, diffuse plaque burden, and vascular amyloid burden associated with all TOMM40 SNPs (p < 0.02). These results suggest that alterations in TOMM40 can promote vascular as well as plaque amyloid deposition, but not the full pathogenic pathway leading to CAA-related ICH.
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21
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Linnertz C, Saunders AM, Lutz MW, Crenshaw DM, Grossman I, Burns DK, Whitfield KE, Hauser MA, McCarthy JJ, Ulmer M, Allingham R, Welsh-Bohmer KA, Roses AD, Chiba-Falek O. Characterization of the poly-T variant in the TOMM40 gene in diverse populations. PLoS One 2012; 7:e30994. [PMID: 22359560 PMCID: PMC3281049 DOI: 10.1371/journal.pone.0030994] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Accepted: 12/28/2011] [Indexed: 11/18/2022] Open
Abstract
We previously discovered that a polymorphic, deoxythymidine-homopolymer (poly-T, rs10524523) in intron 6 of the TOMM40 gene is associated with age-of-onset of Alzheimer's disease and with cognitive performance in elderly. Three allele groups were defined for rs10524523, hereafter ‘523’, based on the number of ‘T’-residues: ‘Short’ (S, T≤19), ‘Long’ (L, 20≤T≤29) and ‘Very Long’ (VL, T≥30). Homopolymers, particularly long homopolymers like ‘523’, are difficult to genotype because ‘slippage’ occurs during PCR-amplification. We initially genotyped this locus by PCR-amplification followed by Sanger-sequencing. However, we recognized the need to develop a higher-throughput genotyping method that is also accurate and reliable. Here we describe a new ‘523’ genotyping assay that is simple and inexpensive to perform in a standard molecular genetics laboratory. The assay is based on the detection of differences in PCR-fragment length using capillary electrophoresis. We discuss technical problems, solutions, and the steps taken for validation. We employed the novel assay to investigate the ‘523’ allele frequencies in different ethnicities. Whites and Hispanics have similar frequencies of S/L/VL alleles (0.45/0.11/0.44 and 0.43/0.09/0.48, respectively). In African-Americans, the frequency of the L-allele (0.10) is similar to Whites and Hispanics; however, the S-allele is more prevalent (0.65) and the VL-allele is concomitantly less frequent (0.25). The allele frequencies determined using the new methodology are compared to previous reports for Ghanaian, Japanese, Korean and Han Chinese cohorts. Finally, we studied the linkage pattern between TOMM40-‘523’ and APOE alleles. In Whites and Hispanics, consistent with previous reports, the L is primarily linked to ε4, while the majority of the VL and S are linked to ε3. Interestingly, in African-Americans, Ghanaians and Japanese, there is an increased frequency of the ‘523’S-APOEε4 haplotype. These data may be used as references for ‘523’ allele and ‘523’-APOE haplotype frequencies in diverse populations for the design of research studies and clinical trials.
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Affiliation(s)
- Colton Linnertz
- Institute for Genome Sciences & Policy, Duke University, Durham, North Carolina, United States of America
| | - Ann M. Saunders
- Deane Drug Discovery Institute, Duke University Medical Center, Durham, North Carolina, United States of America
- Division of Neurology, Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Michael W. Lutz
- Deane Drug Discovery Institute, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Donna M. Crenshaw
- Deane Drug Discovery Institute, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Iris Grossman
- Cabernet Pharmaceuticals, Chapel Hill, North Carolina, United States of America
| | - Daniel K. Burns
- Cabernet Pharmaceuticals, Chapel Hill, North Carolina, United States of America
| | - Keith E. Whitfield
- Department of Psychology and Neuroscience, Duke University, Durham, North Carolina, United States of America
| | - Michael A. Hauser
- Center for Human Genetics, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Jeanette J. McCarthy
- Institute for Genome Sciences & Policy, Duke University, Durham, North Carolina, United States of America
| | - Megan Ulmer
- Center for Human Genetics, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Rand Allingham
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Kathleen A. Welsh-Bohmer
- Joseph and Kathleen Bryan Alzheimer's Disease Research Center, Duke University, Durham, North Carolina, United States of America
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Allen D. Roses
- Institute for Genome Sciences & Policy, Duke University, Durham, North Carolina, United States of America
- Deane Drug Discovery Institute, Duke University Medical Center, Durham, North Carolina, United States of America
- Division of Neurology, Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America
- Joseph and Kathleen Bryan Alzheimer's Disease Research Center, Duke University, Durham, North Carolina, United States of America
| | - Ornit Chiba-Falek
- Institute for Genome Sciences & Policy, Duke University, Durham, North Carolina, United States of America
- Division of Neurology, Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America
- Joseph and Kathleen Bryan Alzheimer's Disease Research Center, Duke University, Durham, North Carolina, United States of America
- * E-mail:
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22
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Vounou M, Janousova E, Wolz R, Stein JL, Thompson PM, Rueckert D, Montana G. Sparse reduced-rank regression detects genetic associations with voxel-wise longitudinal phenotypes in Alzheimer's disease. Neuroimage 2011; 60:700-16. [PMID: 22209813 DOI: 10.1016/j.neuroimage.2011.12.029] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Revised: 11/18/2011] [Accepted: 12/14/2011] [Indexed: 11/17/2022] Open
Abstract
Scanning the entire genome in search of variants related to imaging phenotypes holds great promise in elucidating the genetic etiology of neurodegenerative disorders. Here we discuss the application of a penalized multivariate model, sparse reduced-rank regression (sRRR), for the genome-wide detection of markers associated with voxel-wise longitudinal changes in the brain caused by Alzheimer's disease (AD). Using a sample from the Alzheimer's Disease Neuroimaging Initiative database, we performed three separate studies that each compared two groups of individuals to identify genes associated with disease development and progression. For each comparison we took a two-step approach: initially, using penalized linear discriminant analysis, we identified voxels that provide an imaging signature of the disease with high classification accuracy; then we used this multivariate biomarker as a phenotype in a genome-wide association study, carried out using sRRR. The genetic markers were ranked in order of importance of association to the phenotypes using a data re-sampling approach. Our findings confirmed the key role of the APOE and TOMM40 genes but also highlighted some novel potential associations with AD.
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Affiliation(s)
- Maria Vounou
- Statistics Section, Department of Mathematics, Imperial College London, UK
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23
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Patel S, Shah RJ, Coleman P, Sabbagh M. Potential peripheral biomarkers for the diagnosis of Alzheimer's disease. Int J Alzheimers Dis 2011; 2011:572495. [PMID: 22114744 PMCID: PMC3202136 DOI: 10.4061/2011/572495] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2011] [Revised: 08/17/2011] [Accepted: 08/25/2011] [Indexed: 11/23/2022] Open
Abstract
Advances in the discovery of a peripheral biomarker for the diagnosis of Alzheimer's would provide a way to better detect the onset of this debilitating disease in a manner that is both noninvasive and universally available. This paper examines the current approaches that are being used to discover potential biomarker candidates available in the periphery. The search for a peripheral biomarker that could be utilized diagnostically has resulted in an extensive amount of studies that employ several biological approaches, including the assessment of tissues, genomics, proteomics, epigenetics, and metabolomics. Although a definitive biomarker has yet to be confirmed, advances in the understanding of the mechanisms of the disease and major susceptibility factors have been uncovered and reveal promising possibilities for the future discovery of a useful biomarker.
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Affiliation(s)
- Seema Patel
- Banner Sun Health Research Institute, Sun City, AZ 85351, USA
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Abstract
The completion of the human genome project has led to intensified efforts toward comprehensive analysis of proteomes. New possibilities exist for efficient proteomic technologies. However, primary attention is given to the discovery of new predictive biomarker patterns. Understanding proteomes and, in particular, protein-mediated interactions underlying their complexity and diversity, is critical for the development of more reliable and robust diagnostic platforms, which are anticipated to enable personalized medicine. Of immediate relevance in this respect are those approaches that capitalize on the application of nanotechnology, which is seen as a powerful tool for the diagnosis of early-stage diseases. Here we highlight the current state of the field exemplified by recent nano-enabled technologies for biomarker discovery.
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Ambegaokar SS, Jackson GR. Functional genomic screen and network analysis reveal novel modifiers of tauopathy dissociated from tau phosphorylation. Hum Mol Genet 2011; 20:4947-77. [PMID: 21949350 PMCID: PMC3221533 DOI: 10.1093/hmg/ddr432] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
A functional genetic screen using loss-of-function and gain-of-function alleles was performed to identify modifiers of tau-induced neurotoxicity using the 2N/4R (full-length) isoform of wild-type human tau expressed in the fly retina. We previously reported eye pigment mutations, which create dysfunctional lysosomes, as potent modifiers; here, we report 37 additional genes identified from ∼1900 genes screened, including the kinases shaggy/GSK-3beta, par-1/MARK, CamKI and Mekk1. Tau acts synergistically with Mekk1 and p38 to down-regulate extracellular regulated kinase activity, with a corresponding decrease in AT8 immunoreactivity (pS202/T205), suggesting that tau can participate in signaling pathways to regulate its own kinases. Modifiers showed poor correlation with tau phosphorylation (using the AT8, 12E8 and AT270 epitopes); moreover, tested suppressors of wild-type tau were equally effective in suppressing toxicity of a phosphorylation-resistant S11A tau construct, demonstrating that changes in tau phosphorylation state are not required to suppress or enhance its toxicity. Genes related to autophagy, the cell cycle, RNA-associated proteins and chromatin-binding proteins constitute a large percentage of identified modifiers. Other functional categories identified include mitochondrial proteins, lipid trafficking, Golgi proteins, kinesins and dynein and the Hsp70/Hsp90-organizing protein (Hop). Network analysis uncovered several other genes highly associated with the functional modifiers, including genes related to the PI3K, Notch, BMP/TGF-β and Hedgehog pathways, and nuclear trafficking. Activity of GSK-3β is strongly upregulated due to TDP-43 expression, and reduced GSK-3β dosage is also a common suppressor of Aβ42 and TDP-43 toxicity. These findings suggest therapeutic targets other than mitigation of tau phosphorylation.
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Affiliation(s)
- Surendra S Ambegaokar
- Department of Neurology, University of Texas Medical Branch, 301 University Blvd., MRB 10.138, Galveston, TX 77555, USA
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Abstract
For personalized medicine to be widely adopted in clinical practice, stakeholders need evidence of effectiveness, cost effectiveness and financial viability. Comparative effectiveness research (CER) using population based, retrospective data can inform assessments of personalized medicine. The purpose of this paper is to explore the potential and the limitations of CER. While the analytic methods and data used for CER overcome many of the disadvantages of randomized controlled trials, there are significant barriers, including lack of routinely collected genetic information, patient-reported outcomes and information on new and emerging technologies. Recommendations for using CER include augmenting current data with genetic information, promoting the collection of uniform health outcomes, using value of information analysis to guide development of new technologies, and greater use of decision analysis. Finally, in order to address stakeholder concerns regarding short term financial viability, additional emphasis should be devoted to cost analysis of implementation costs and overall financial impact.
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Mandel SA, Morelli M, Halperin I, Korczyn AD. Biomarkers for prediction and targeted prevention of Alzheimer's and Parkinson's diseases: evaluation of drug clinical efficacy. EPMA J 2010. [PMID: 23199065 PMCID: PMC3405324 DOI: 10.1007/s13167-010-0036-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Neurodegenerative diseases like Parkinson’s disease (PD) and Alzheimer’s disease (AD) are considered disorders of multifactorial origin, inevitably progressive and having a long preclinical period. Therefore, the availability of biological markers or biomarkers (BMs) for early disease diagnosis will impact the management of AD and PD in several dimensions; it will 1) help to capture high-risk individuals before symptoms develop, a stage where prevention efforts might be expected to have their greatest impact; 2) provide a measure of disease progression that can be evaluated objectively, while clinical measures are much less accurate; 3) help to discriminate between true AD or PD and other causes of a similar clinical syndrome; 4) delineate pathophysiological processes responsible for the disease; 5) determine the clinical efficacy of novel, disease-modifying (neuroprotective) strategies. In the long run the availability of reliable BMs will significantly advance the research and therapeutics of AD and PD.
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Affiliation(s)
- Silvia A. Mandel
- Eve Topf Center for Neurodegenerative Diseases Research and Department of Molecular Pharmacology, Faculty of Medicine, Technion, Haifa, Israel
| | - Micaela Morelli
- Department of Toxicology and Centre of Excellence for Neurobiology of Dependence, University of Cagliari, Cagliari, Italy
| | - Ilan Halperin
- The Israeli Psycological Association, Beersheba, Israel
| | - Amos D. Korczyn
- Tel-Aviv University Medical School Sieratzki Chair of Neurology, Ramat-Aviv, Israel
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Abstract
Current figures: About 300 million Diabetics frequently affected by Poly-Neuropathy as secondary complication, 18 million patients with Alzheimer’s disease also diagnosed as Diabetes Type 3, neurodegenerative eye diseases with leading causes of blindness—diabetic retinopathy and estimated 67 million glaucoma patients worldwide, millions of patients with Parkinson’s disease, Multiple Sclerosis, Epilepsy, Cerebral Palsy and Dementia in the elderly—altogether dramatically affect life quality, social and economical indexes of populations around the globe. Optimistic versus Pessimistic Prognosis depends much on diagnostic, preventive and treatment approaches which healthcare will preferably adopt in the near future. Without innovation in healthcare, neurodegenerative disorders can reach more than 30% of global disease burden till 2020. In contrast, effective utilisation of advanced early/predictive diagnostics, preventive and personalised medical approaches could enable a significant portion of population to reach the 100-year age limit remaining vibrant in excellent physical and mental health as actively contributing members of society.
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Affiliation(s)
- Olga Golubnitschaja
- Department of Radiology, Rheinische Friedrich-Wilhelms-University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany ; European Association for Predictive, Preventive & Personalised Medicine, Brussels, Belgium
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